Saskatchewan earthquakes occur most often near Esterhazy
Seismologist says geological formation, rather than mining, likely cause
A seismologist says earthquakes are fairly rare in Saskatchewan, but when they do occur, it's often in the same area that had a 3.8 magnitude earthquake on Monday, east of Yorkton.
Andrew Frederikson, a seismologist at the University of Manitoba, said about half of the 49 earthquakes registered in Saskatchewan by the federal Geological Survey of Canada since 1985, have happened in the Esterhazy area.
Frederikson said the earthquakes are not due to potash mining itself, so much as the makeup of the earth in the area, which also happens to allow for potash mining.
"Some of these earthquakes may be what are called induced, [in] that they're related to human activities. But probably not all of them," Frederikson said.
He said what is known as the prairie evaporite formation, which contains potash and other dissolvable minerals, seems to be more prone to earthquakes.
"They're not necessarily concentrated where the most mining is. They're specifically concentrated on the edge of the evaporite, which suggests that there's some sort of dissolution effect going on."
"Particularly this cluster just sort of east of Esterhazy which might have something to do with what the groundwater is doing there. Maybe there's just more groundwater interacting with the evaporite formation in that region," he told CBC Radio's The Morning Edition.
According to Frederikson, the prairie evaporite formation runs through a big chunk of the prairies, but it is the outer edge of it that is most prone to earthquakes.
with files from The Morning Edition